It said several of Samsung’s devices had infringed iPhone-maker Apple’s software and design patents.
The jury rejected Samsung’s claims that several of its patents had been breached and awarded it no damages.
Apple may seek an import ban of some of its rival’s products, blocking them from the US market. Samsung has said it will appeal against the ruling.
“We will move immediately to file post-verdict motions to overturn this decision in this court and if we are not successful, we will appeal this decision to the Court of Appeals,” a statement from Samsung said.
Apple and Samsung account for more than half of global smartphone and tablet computer sales.
The nine-person jury at the federal court in San Jose, California had to consider 700 questions about each side’s claim that its rival had infringed its intellectual property.
It deliberated for less than three days before coming to its unanimous decisions.
It rejected the South Korean firm’s claim that Apple’s intellectual properties were invalid. It added that Samsung was “wilful in its infringement” in many of the cases.
Not all of Apple’s claims were upheld – it had claimed a total of $2.5bn (£1.6bn) in damages. Samsung had sought $519m.
Apple said it applauded the court “for finding Samsung’s behaviour wilful and for sending a loud and clear message that stealing isn’t right.”
Samsung described the verdict as “a loss for the American consumer”.
“It will lead to fewer choices, less innovation, and potentially higher prices,” it added.
The jury ruled that some of Samsung’s handsets, including its Galaxy S 4G model, had infringed Apple’s design patents for the look of its iPhone including the system it uses to display text and icons.
However, it dismissed the allegation that the South Korean firm’s tablets had infringed the rectangular design used for Apple’s iPad.
It also found that all the disputed Samsung devices had copied the bounce-back response in the iOS system’s user interface, without paying a licence. This makes lists jump back as if yanked by a rubber band when pulled beyond their limit.
Another infringement involved use of Apple’s tap-to-zoom feature.
Samsung failed to convince the jury Apple owed it money for using technologies it claims to own including listening to music on a device in the background while carrying out another task; and integrating a phone, digital camera and email facility into a single device.
Michael Gartenburg, research director at Gartner, said the verdict could have major ramifications for the wider smart device sector.
“Apple patents being upheld will force the rest of the industry to both innovation and differentiation,” he said.
“That will be a good thing for consumers in the long run. Anyone who was even thinking about borrowing a technology or design from Apple will think twice about it now.
“Apple’s point was that it was possible to create an experience that doesn’t look like its designs and only Nokia and RIM Blackberry are really doing that right now.”
There has been a spate of lawsuits involving mobile-device makers, but this case had been viewed as one of the most significant to date.
This is because of the size of the damages involved, the likelihood it will influence the way future patent licenses are handled, and the insights it has given into both Apple and Samsung’s working practices.
Pictures of prototype iPhones and iPads that had never been seen before were released, and one of Samsung’s designers explained how she had created some of its app icon designs.
The offending Samsung models at the centre of the case have since been superseded by updates, reflecting the fast turnaround in product releases.
But Apple said it still intended to seek sales injunctions at a follow-up hearing on 20 September.
It may also seek to use this ruling to block other devices powered by Google’s Android software that it believes replicate elements of its user-interface, including current models by Samsung as well as other firms.
While Apple has scored a victory over Samsung, it remains one of the South Korean company’s biggest customers buying computer chips and, reportedly, screens from it to build the iOS mobile devices.
Image source: Wikimedia Commons President-elect Donald Trump celebrated his election victory at the Ultimate Fighting…
Millions of voters across the US chose to return Donald Trump to the White House…
Donald Trump declares victory in the US election as he addresses jubilant supporters in Florida.…
Stocks around the world are rising as Donald Trump appears to be on the cusp…
Donald Trump has won Pennsylvania, North Carolina and Georgia and taken a lead over Kamala…
Quincy Jones, the celebrated musician and producer who worked with Michael Jackson, Frank Sinatra, Ray…